Epinephrine (also called adrenaline), by its most commonly used chemical name 4-[1-hydroxy-2-(methylamino)ethyl]-1,2-benzenediol, is a known, commercially available compound. Its l-form has adrenergic properties, and together with its dipivalate [di(trimethylacetate)] ester derivative, propine, is a clinically useful anti-glaucoma agent. These compounds also cause mydriasis, an excessive dilation of the pupil of the patient's eye upon administration.
Beta-adrenergic blocking agents (.beta.-blockers) are structurally similar to epinephrine derivatives and, indeed, their certain representatives such as 1-[(1,1-dimethylethyl)-amino]-3-{[4-morpholinyl-1,2,5-thiadiazol-3-yl]oxy} -2-propanol (timolol); 1-{4-[2-(cyclopropylmethoxy)ethyl]phenoxy}-3-[(1-methylethyl)amino]-2-prop anol (betaxolol) and 5-[3-(terbutylamino)-2-hydroxypropoxy]-3,4-dihydro-1(2H) -nathalenone (bunolol), lower intraocular pressure.
Typical representatives of another class of known anti-glaucoma agents (muscarinics) are pilocarpine [(3S,4R)-3-ethyl-4-[(1-methyl-1H-imidazol-5-yl)methyl]-3,4-dihydro-2(3H)-f uranone], and its pyrrolidinone derivative, (3R, 4R) 3-ethyl-4-[(1-methyl-1H-imidazole-5-yl)methyl]-2-pyrrolidinone. The latter compound, together with other, 1-alkyl substituted derivatives, is disclosed in the U.S. Pat. No. 3,470,197 See also Koda, et al., J. Pharm. Sci. 62, 2021 (1973) who describe certain of these compounds as possessing cholinergic activity.
Muscarinics lower intraocular pressure via contraction of the ciliary muscle, and as a side-effect, also cause simultaneous contraction of the iris muscle leading to miosis in the patient's eye.